Or, back, last year, I used to try to prove all my teachers wrong, so before class would start I'd go up to the board and misspell a bunch of random stuff he/she had up, and then call them out on it in the middle of a discussion. <<they got pretty darn annoyed at that.

Too many times :/
I remember laughing so much I was crying in year 9, and the teacher sent me out but then she forgot about me T__T I missed the whole lesson XD

Once we were writing up coursework which I totally wasn't in the mood for and my teacher said "If you're not here to work then get out!"
I dunno if he meant it seriously or not, but I took it as a chance to escape D:

yer i always get sent out of class by the shit teachers but not with the mad teachers. i was in class one day with my mate and i got this guy with a paper wasp in the face and he started to swear at me and the teacher gave him a green card (has to be good 4 one week or he will be suspended)

LOL Yeah!
back when i was in elementary.
first when i got into an argument with my guy or gay classmate.
second when my 2 seatmates & I forgot to bring a dice for our math activity. but i was sent back first 'coz i behaved.
and the third time, i forgot what we did but majority of our class were sent out.lol